Category Archives: Environmental Pollution

Termites to the Rescue

White ants could offer a solution to the problems of global warming. T.V. Jayan reports

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It is one of the most destructive species ever known. It can turn houses to dust in a very short time and chomp its way through huge quantities of wood or paper at a frightening speed, posing an enormous threat to homes and offices. But although the termite problem causes billions of dollars in damage every year, the tiny insects — also called white ants — may actually help find a solution to a major problem mankind faces today — climate change.

Even as thousands of climate scientists and policy hawks from all over the world meet for yet another biennial jamboree on the beautiful island of Bali, trying to figure out better ways of cutting the emissions of carbon dioxide and other gases that heat up the earth, microbiologists working on termites — collected from the evergreen rain forests of Costa Rica — offer a glimmer of hope. The way to a greener biofuel future is through the tummy of termites, they claim in a recent issue of Nature.

The work, spearheaded by researchers at the California-based Joint Genome Institute — part of the US Department of Energy — reveals the remarkable metabolic machinery that helps termites digest hardy plant materials with amazing efficiency.

Termites can devour wood because their bellies harbour more than 200 unique microbes whose concerted action helps break down the stuff. This consortium of microbes works in tandem with chemicals generated in their gut to produce an ensemble of enzymes that are so far the most efficient biochemical means to digest wood.

If scientists can crack the genetic code and synthesise these novel enzymes on an industrial scale, it would make for one of the best available methods to efficiently convert wood or waste biomass into valuable biofuels.

A United Nations Development Programme report released last week touted biofuels such as ethanol and biodiesel as a viable energy option to mitigate the threat of climate change because, unlike fossil fuels like petroleum, they are carbon neutral. Carbon dioxide, released into the atmosphere by biofuel burning, is of recent origin and is hence part of the ongoing carbon cycle. Using fossil fuels, on the other hand, releases carbon dioxide that has been sequestered for millions of years as oil or coal, adding to the carbon dioxide build up in the atmosphere.

The rain forests of Costa Rica are a well known hotbed of biodiversity for termites. The “higher” termites that the scientists chose, to further the frontiers of science, belong to the genus Nasutitermes.

While termites have been the subject of keen scientific study for more than a century, the precise identity and role of the microbes in their digestive tract remained a mystery. The current work, a collaborative effort among scientists from the US, Costa Rica and Germany, is the first to throw light on the symbiotic orchestration that goes on in the belly of white ants.

Termites eat wood, but they can’t extract energy from the complex lignocellulose polymers within it. These polymers are broken down into simple sugars by fermenting bacteria in their gut, using enzymes that produce hydrogen as a byproduct. A second wave of bacteria uses the simple sugars and hydrogen to make the acetate the termites require for energy.

Another remarkable finding was that like cows, termites too have a series of stomachs, each home to a distinct community of microbes that have specifically assigned jobs along the conversion pathway of woody polymers to sugars. The real work is carried out in the rear portion of the gut, where the enzymatic juices exuded by the bacteria attack and break down cellulose and hemicellulose which along with lignin form the basic building blocks of wood.

Subsequently, the scientists extracted and purified the contents of the third paunch, or hindgut, of more than 150 worker termites, mapping the extract to ascertain their genetic content.

“Our analysis revealed that the hindgut is dominated by two major bacterial lineages — treponemes and fibrobacters,” said Philip Hugenholtz, who heads JGI’s microbial ecology research. While it was earlier known that treponemes exist in the termite gut, fibrobacters were an exciting new find, he remarked. Their relatives found in the cow rumen are excellent in degrading cellulose.

While experts feel that cellulose can be an excellent raw material for producing energy, as it is theoretically a great source of hydrogen, extracting hydrogen — the cleanest possible fuel — is difficult because it requires a huge amount of energy and money.

But termites do the job exceedingly well, without using harsh chemicals or excess heat, thanks to their microbial guests. Theoretically speaking, termites can convert a sheet of A4 paper into two litres of hydrogen, said Andreas Brune, a biogeochemist at Germany’s Max Plank Institute for Terrestrial Microbiology in Marburg. Cranking up such a large amount of hydrogen from a cellulose source (the main content of paper is cellulose) calls for unbelievably high efficiency. As a result, termites are often referred to as one of the most efficient bioreactors in Nature.

Figuring out which enzymes are used to create hydrogen and which genes produce them is the first step towards developing a process that can help generate hydrogen commercially from biomass.

“To get there, we must first define the set of genes with functional attributes for the breakdown of cellulose. This study represents an essential step along that path,” said Edward Rubin, JGI director.

Sources: The Telegraph (Kolkata, India)

25 Resources to Help You Reduce, Recycle, and Reuse Plastic Bags

 

In case you did not already realize it, the one trillion plastic grocery bags used worldwide every year are becoming a serious drain on the environment.

21st Century Citizen
has compiled a great list of the Top 25 resources to help you reduce, recycle, or reuse all those plastic bags you carry home from your grocery store.

Their list includes creative gems like:

  • Where to find a recycling location near you, in case your local grocery does not offer a recycling bin

  • Sites that sell reusable shopping totes

  • Creative ideas for reusing plastic bags for other things around your house

  • Novel classroom projects for teachers

  • Patterns for turning plastic bags into reusable items such as hefty tote bags and all-weather rugs

With so many options, there’s bound to be a solution that works for you, reducing your environmental impact, and saving you money in the process! For the full list, check out the source link below.

Sources: 21st Century Citizen

Diesel pollution could harm heart

NEW YORK: A study by US researchers suggests that diesel fumes appear to raise the risk of heart disease in people with high cholesterol.

The researchers combined the pollutants and fats and cultured them with cells taken from the inner lining of human blood vessels. A few hours later, they extracted DNA from the cells for genetic analysis.

They showed that the genes that promote cellular inflammation had been activated, reported the online edition of the BBC news.

Next, they exposed mice with high cholesterol to the diesel particles and saw that some of the same genes were activated in the animals’ tissue.

The scientists, however, said they could not understand exactly how air pollutants cause cardiovascular injury.

“But we do know that these particles are coated with chemicals that damage tissue and cause inflammation of the nose and lungs” University of California, Los Angeles researcher André Nel said.

“Vascular inflammation in turn leads to cholesterol deposits and clogged arteries, which can give rise to blood clots that trigger heart attack or stroke,” Nel added.

Scientists said that the damaging particles in diesel fumes and the cholesterol act in combination to switch on genes that cause potentially dangerous inflammation of the blood vessels.

Their combination creates a dangerous synergy that wreaks cardiovascular havoc far beyond what’s caused by the diesel or cholesterol alone.

Source: The Times Of India

WHO warns on global warming!

KUALA LUMPUR: The World Health Organisation warned that global policy makers must act quickly to address the critical problem of global warming, or face serious health and economic consequences.

Shigeru Omi, WHO’s regional director for the Western Pacific region, said the current crisis was masked by the fact that global warming issues did not present as much a tangible problem to many governments, as compared to immediate health problems such as communicable diseases.

However, he warned that the international community needed to take the issues seriously to avert what would be definite health implications caused by global warming.

“For environmental issues, if you wait for the crash to happen, it’s already too late.

“We know it is just a matter of time, and unless we take measures disaster will come,” Omi said.

“So far, it’s already causing health issues, but if this trend continues, it will upset the economies of the world,” he said.

“We should not wait for that to happen.”

Earlier, Omi told delegates that climate change has been responsible for adversely affecting the health and lives of populations across Asia, from destruction of crops to increasing rate of diseases.

“Increasing temperatures are among the variables that affect malaria and the disease is emerging in places where it did not exist before,” he said in his opening speech.

Omi cited that in Singapore, the annual temperature rose by 1.5 degrees centigrade in 20 years. In the corresponding times, the number of the mosquito-borne dengue fever cases increased more than 10-fold from 384 in 1978 to 5,258 in 1998.

The WHO had released a statement last week saying that an estimated 77,000 deaths are recorded annually in the Asia-Pacific region due to health problems arising from global warming.

The health agency also estimates that about one quarter of the global burden of disease is due to modifiable environmental factors including climate change.

“The global community has become more and more aware of the environmental issues,” said Omi.

“Certainly, the level is higher than say three years ago.

“But a lot more political will is needed. Now is the time to give more attention and focus to global warming issues,” he told reporters.

More than 60 health experts have gathered in Kuala Lumpur to discuss the effects of increasing global temperatures. Key findings of the workshop would be shared at a ministerial meeting in Bangkok on August 8 and 9.

Source:The Timers Of India

Global warming claims 77,000 lives

KUALA LUMPUR: The World Health Organization said Thursday that an estimated 77,000 deaths are recorded annually in the Asia-Pacific region due to health problems arising from global warming.

The statement by the world health body comes ahead of next week’s meeting of international health experts from 14 different nations at Malaysia’s capital Kuala Lumpur to discuss the effects of increasing global temperatures.

“We have now reached a critical stage in which global warming has already seriously impacted lives and health, and this problem will pose an even greater threat to mankind in coming decades if we fail to act now,” Shigeru Omi, WHO regional director for the Western Pacific, was quoted as saying in the statement.

Among the potential effects of global warming would be the appearance of mosquitoes in areas where they were previously absent, with the accompanying threat of malaria and dengue fever.

The conference will also reveal that some regions might be at risk of reduced rainfall, causing a shortage of fresh water and introducing the danger of waterborne diseases.

Millions of people could be at risk of malnutrition and hunger if arable lands become unworkable, the statement warned.

Delegates at the four-day conference will also be told that the increasing frequency of summer heat waves in temperate zones, and typhoons, hurricanes and floods throughout the world are signs of changing weather and climate patterns.

Key findings from this workshop will be shared at a ministerial meeting in Bangkok on August 8 and 9, which will be attended by ministers of health and environment from 14 countries in the Southeast and East Asia regions.

Source:The Times Of India